Artificial leg



Aug. 24 1926.

F. BUCHSTEIN ARTIFICIAL LEG Filed Sept. 11, 1922 Patented Aug. 24, 1926.

UNITED, STATES PATENT OFFICE. 1

ARTIFICIAL LEG.

Application filed September 11, 1922'. Serial No. 587,505.

My present invention relates to improvements in artificial limbs for amputations below the knee, and has for one of its objects to provide a knee strap attachment therefor to throw the leg forward and thereby give a natural knee movement. A further object of the attachment is to firmly hold the artificial leg to the stump so that it will not work up and down and, hence, will prevent chafing. A still further object of the invention is to provide means whereby the individual carries an artificial limp in part from his thigh, just above the knee cap, instead of entirely from his shoulders, by means of suspenders.

To the above end, generally stated, the 1nvention consists of the novel devices and combinations of devices hereinafter described and defined in the claims.

In the accompanying drawings, which illustrate the invention, like characters indi cate like parts throughout the several views.

Referring tothe drawings:

Fig. 1 is a perspective view of an artificial leg for an amputation below the knee, and has the invention applied thereto;

Fig. 2 is a fragmentary rear View of the same; and

Fig. 3 is a plan view of the knee strap attachment removed from the artificial leg.

The artificial leg illustrated is for amputations below the knee, and of the parts thereof, it is important to note the shank 4, socket 5, thigh lacer 6, and side knee oints '7 formed by pivotally connecting upper and lower metal straps 8 and 9, respectively, and which straps 8 and 9 are secured, respectively, to the thigh lacer 6 and shank 4, at the inner and outer sides thereof. The parts thus far described are of standard and well known construction.

Referring now in detail to my invention, the numeral 10 indicates a yoke-like strap arranged to straddle the thigh 11 of the wearer, just above the knee cap 12 and below the thigh lacer 6. The prongs 13 of the strap 10 are attached, one to each side of the shank 4: by head stubs 14: which may be inserted through any one of a plurality of longitudinally spaced holes 15 in the lower end portions of said prongs to adjustably connect the same, as to length,

to the shank 4.

It is important to note that the prongs 13 of the knee strap 10 are attached to the shank 4; back of the vertical plane in which the axes of the pivots of the side kneejoints 7 are located. .It is also important to note that the prongs 13 of the strap 10, at the top of the socket 5, are held back of the axes of the pivots for the side knee joint 7, and as a convenient means of doing this, said prongs are extended inside of the side knee joints 7 and engage the back edges of the straps 9 at the top of the socket 5. Various other means may be provided for thus holding the prongs 13 in proper position.

The, lower end of an elastic webbing is attached to the transverse portion of the strap 10 and has on its upper end a buckle 17 which adjustably holds: a billet 18 secured to a pair of suspenders, or belt not shown.

The purpose of extending the prongs of the yoke-like strap 10 back of the side knee straps 9 is to hold said straps drawn backward around the leg and thereby hold the socket 5 so that the stump will not move therein, thus permitting the wearer, when walking, to give the artificial lower leg section a natural walking motion by means of the stump, regardless of its length. By thus holding the socket 5 on the stump there will be no movement of the stump in the socket that will produce chafing. This peculiarapplication of the yoke-like strap 10 to the wearers leg permits him to carry the greater part of the weight of the artificial leg from the leg to which it is applied which is the natural way the weight should be carried instead from the shoulders by means of suspenders.

'The above described invention has, in

actual usage, proven highly efficient for the purpose had in view.

What I claim is:

1. The combination with an artificial leg having a shank with a socket adapted to re ceive the stump of a lower leg amputation, and side knee joints attached to the shank, of a yoke-like knee strap arranged to straddle the patella in the vicinity of the knee joint, the end portions of said strap being attached to the shank and held at the topthereof back of the side knee joints for holding said strap aroundthe leg to prevent movement of its stump in said socket.

2'. The combination with an artificial leg having a shank with a socket adapted to receive the sttunp of a lower leg amputation, and side knee joints attached to the shank, of a yoke-like knee strap arranged to stradthigh lacer, of a yoke-like knee strap arranged to straddle the" patella in-the vicinity of the knee joint, the end of the strap be ing attached to; the sides of the shank below the top thereof, the end portions of said strap being extended back of the knee joints and engaging the same as stops to draw the end portions'of the strap backward and prevent forward movement thereof.

-In' testimony whereofil affix'my signature.

'FERDINAND BUGHSTEIN. 

